The story
The firm was founded by Charles Merz and William McLellan in Newcastle upon Tyne in 1902 when McLellan joined Merz's existing firm established in 1899. The partnership was instrumental in designing the United Kingdom's first three-phase electrical supply network, on Tyneside and, for the next century, continued to advise other Commonwealth countries on setting up their own networks.
In the early 1960s, Merz & McLellan started a scheme in the interest of reclaiming land owned by the London Brick Company in Peterborough; James Price took up the position of senior resident engineer. That became known as the "Peterborough Dust Disposal Scheme".
In 1995, the partnership merged with the Parsons Brinckerhoff consultancy and, in 2000, the new owners announced that the Merz & McLellan name would be discontinued.
In 2010, Mott MacDonald consultancy announced that it had bought Merz and McLellan South Africa.
From Wikipedia’s article on Merz & McLellan, shared under CC BY-SA 4.0.3